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Wait but decelerating forever does in fact imply recollapse doesn't it?
by Erem 11mo ago
Wait but decelerating forever does in fact imply recollapse doesn't it?
- deepthaw 11mo agoI assume decelerating forever means asymptotically approaching not collapsing.
- pdonis 11mo agoNo. The simplest example is a matter-dominated universe at exactly the critical density. It decelerates forever but never quite stops expanding--the expansion rate asymptotes to zero.
- cwillu 11mo agoAn object on an escape trajectory from another mass is forever decelerating, but it still escapes.
- jimbo808 11mo agoWould it not enter the viscinity of other objects which would eventually coalesce into local centers of mass (maybe like one per observable universe diameter or something)?
- ridgeguy 11mo agoNope, cosmic Zeno's Paradox. Collapse never quite happens.
- xerox13ster 11mo agoNope, that would be velocity changing sign, which means acceleration would increase.
- SideburnsOfDoom 11mo agoNo, in much the same way that a speeding vehicle slowly decelerating towards a stop doesn't mean that it will return to where it started the journey. Actually it's worse than that, "decelerating forever" doesn't even mean that it ever even comes entirely to a stop. let alone return to where it started.